Improvement in repeating actions for pianos



F. POLSTER.

Repeating-Action for Pianos.

Patented Feb. 16,1875.

WJVK" &SS ES HE GRAPHIC CO.PNOT0-LITH.39&41PARK PLACE,N.Y.

UNITED STATES PATENT OFFICE FERDINAND POLSTER, OF BALTIMORE, MARYLAND.

IMPROVEMENT IN REPEATING ACTIONS FOR PIANOS.

Specification forming part of Letters Patent No. 1 59338, dated February16, 1875 application filed October 28, 1874.

To all whom it may concem:

Be it known that I, FERDINAND POLSTER, of Baltimore, in the county ofBaltimore and State of M aryland, have invented a new and ValuableImprovement in the Repeating Action of Pianos; and I do hereby declarethat the following is a full, clear, and exact description of theConstruction and operation of the same, reference being had to theannexed drawings making a part of this speoification, and to the lettersand figures of reference marked thereon.

Figure l of the drawings is a represeutation of a side elevation of asingle key-lover With its attachments, showing my spring devices actingin combination with the repeatingstandard, the 'fly and key levers, andthe flylever bottom; also, the rails and key-board in section. Fig. 2represents a perspeetive view of regulating tenon-rocker butt, with itsresilient spring and bufer-head.

My invention is a device for produeing a ready and rapidly repeatingaction in pianos; and consists in the novel construction and operationof the same, for the purpose aforesaid, and embraces the followingpeeuliar features: A regulated resilient spring supporting thehammer-standard, and, by means of buffers, roeker-butts, and set-screws,coactin g with said standard and the fly and key levers of a pianoforteaction; also, a bent and twisted spring, supporting and springing thelower arm of the fiy-lever, all of which and their purposes arehereinafter more full y described and illustrated by the aeeompanyingdrawings, in which the same letters designate identioal parts of mydevice in the different figures, respeotively.

The letter A represents the usual keyboard of a piano, suitablysupporting the key-lover 3. G is the rooler-lever bottom or butt,attaehed to and regulated upon the aforesaid key-lover, and hinged atits inner end to the fulcrum of the usual fly-lever D, all in the usualmanner. Said fly-lever has an elbow shape, with a Vertical andhorizontal arm, as

illustrated. E is the usual hammer backcheck. F is the usual hammer, andI) its butt, resting upon the hammer-rail c. H is the hammer-standard,which generally rests, by means of the notch e, upon the top of thevertieal arm of the said fiy-lever. I is one of the musical strings ofthe piano. K is the'usual rail for the support of the hammer F when atrest, and provided with the usual set-screw and bnfer f to press downthe horizontal arm of the fly-lever, and also regulate the eXtcnt of theconseqnent oscillation of its vertical arni.

The above usual elements of the best pianoactions now made have incombination and coaction with them certain new elements, as follows: Aspring, L, consisting of a rod of resilient metal of' suitable size andlength, having one end firmly and tightly inserted into a rochig butt orblock, g, and the other end similarly inserted into a head or tongue, h,as illustrated, the whole forming a resilient and bufer spring under thefoot of the aioresaid standard H, and supported and regulated upon thekey-lever B by means of the setscrews t' and the tenon-rocker k. Thesaid tongue h extends underneath the inner end of the lever-butt 0, forthe purpose of preventing the said tongue from springing up to'o high,and thus pressing the hammer F against the string I. Also, inserted intothe foot of the said standard H is one end of another setscrew, m, theother end of which is passed down loosely through a hole, a, piereedthrough the said tongue lt, and into another hole made directlyunderneath the former into the upper edge of the key-level* B. Thisset-screw m is thus arranged for the purpose of keeping the standard Halways in a vertical position while raising or lowering the hammer F 5and it is provided also with a butter-block, l, which rests upon thetongue h, and thus wholly supports said standard when the top of thevertical arm of the aforesaid fiy-lever is out of the notch e, while italso, by being turned up or down upon the screw-threads, regulates theoscillation and momentum of the aforesaid hammer. The letter srepresents another spring, eonsisting of a piece of resilient wre ofsuitable length and size twisted once or twice upon itself, and bentinto an elbow shape, as illustrated. The end of the shorter arni of saidelbow is inserted tightly into the top of the outer end of the fly-leverbutt G, and the end of the other arm passed underneath the horizontalarm of said fiy-lever D, for the purpose of springing the top of thevertical arn of the same into the notch e, when the inner end of' thekey-level* B comes down, and the hammer F falls into rest.

Hence the operation of the aforesaid sprin gs, as shown, in conhinationwith the said older elements, produces" a ready and rapidly-repeatigaction of the hammer upon the strings, should the performer even presscontinuously upon the key, and make ever so rapid a trilling vibrationof the string-a result much desired, but hitlerto unattained; therefore,

What I claim as my invention, and desire to secure by Letters Patent, is

In piano-forte actions, the resilient spring

